Process for separating the first and last runnings in distillation and rectification.



F. PAMPE, DECD.

E. J. J. PAMPE, WIDOW & P. B. 0. A. & 0. A. R- PAMPE, SONS.

PROCESS FOR SEPARATING THE FIRST AND LAST RUNNINGSIN DISTILLATION AND RECTIFICATIO N.

APPLICATION FlLED-APR.I8.1905- RENE-WED MAY 28. 1915.

1,145,332. PatentedJuly 6,1915.

Fi g1. 36

FRANZ PAMPE, OF HALLE-ON-THE-SAALE, GERMANY; ELEONORE JOSEFINE JOHANNA PAMPE, WIDOW, ONE-FOURTH INTEREST, PHIL-BRUNO OTTO ALEXANDER PAMPE, SON, THREE-EIGHTHS INTEREST, AND OTTO ALFRED ROBERT PAMPE, SON, THREE- EIGI-ITHS INTEREST OF THE ESTATE OF SAID FRANZ PAMPE, DECEASED.

PROCESS FOR SEPARATING THE FIRST AND LAST RUNNINGS IN DISTILLATION AND RECTIFICATION.

Specification of Letters Patent. I Patented July 6, 1915;.

Application filed April 18, 1905, Serial No. 256,2?7. Renewed May 28, 1915. Serial No. 31,088.

To aZl whom it may concern Be it known that I, FRANZ PAMPE, a subject of the King of Prussia, German Emperor, residing at the city of Halle-on-thebaale, in the Kingdom of Prussia, German Empire, have invented certain new and useful Improvements in Processes for Separating the First and Last Runnings in Distillation and Rectification; and I do hereby de clare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

My invention has reference to a process for the distillation and rectification of alcohol, its subject matter consisting of a process for the elimination of the fusel oils during said distillation and rectification.

During the distillation and rectificatlon of alcohol the fusel oils are present in the distilling and rectifying column respectively in an undissolved condition, in the lower portion thereof where there is a mixture of alcohol and water having so low a percent-- ageof the former that it is incapable of dissolving the fusel oils. When subjected to heat the fusel oils in, this part of the column are, consequently, almost entirely evaporated and ascend in the form of vapor into the parts of the column lying immediately above. In conjunction with these fusel oil vapors those of theevaporated alcohol also ascend at the same time into the upper portions of the column; here the percentage of alcohol in the ascending vapors gradually increases so that, at a predetermined point,

the fusel oils-are dissolved by the stronger alcohol. After the fusel oils have been dissolved by the alcohol, it becomes still more difficult to eliminate and remove'them from the column; the molecules of the alcohol exert a certain attraction upon those of the fusel oil. In addition to this the fusel oils,

after their final solution in alcohol, form solutions from which the fusel oils can no longer be evaporated away. In view of this,

where the fusel oils are not yet dissolved,

but are on the very verge of being dissolved.

In this dividing layer a most favorable op portunity is afforded for withdrawing the fusel oils from the column. Undoubtedly the fusel oils are also in an undissolved state 1n the lower portions of the column, but it is not an easy matter to remove them at that point, because the fusel oil vapors tend to ascend rapidly into the upper portions of the column. If, however, certain small quantities of fusel oils should become separated from the alcohol in those parts of the column lying above the dividing layer, andthere become vaporized, still they would in most cases become incorporated with the liquid (a mixture of alcohol and water) flowing downward in the column; this stream would carry them along with it and so conduct-them to the dividing layer. The dividing'layer lies in the distilling column between its fifth to tenth floor counting from the bottom upward, provided the distilling column be about 9 meters high, possesses about 40 floors and if said floors are at a dis tance of 0.20.3 meters from each other.

Now, the novel feature of my invention is tobe found in the essential characteristic that steam is admittedat one side of the dividing layer, in the distilling or rectifying column, and is allowed to escape atinto the column a littlebelow the point at which the fusel oils pass from the undissolved into the dissolved state (i. e. at the dividing layer) the said steam being withdrawn from the column, at a point lying opposite that at which it was introduced, together with the undissolved fusel oil vapors that have collected there. On passing the steam through the column it absorbs only very little alcoholic vapor, whereas almost the whole of the fusel oils are carried away with it.

Methods are already known for the removal of fusel oils, whereby water or steam is passed into the alcoholic liquid. In the case of these processes warm water or steam is introduced into the column, at that point thereof where the fusel oils collect in a liquid form, in such large quantities that consequently a much lower percentage of alcohol is contained not only in the liquid in the column, but also in the vapors thrown bif thereby. Due to this lower percentage of alcohol, however, the solubility of the fusel oils in the mixture of alcohol and water is greatly inferior; the fusel oils separate consequently from the water with greater ease, and they therefore rise in a liquid form to the surface of the liquid which is drawn off laterally through a union. Still the liquid left behind is saturated with fusel oils, and only the superfluous portion can. be eliminated. Hence the vapors coming from below and rising upward from the bottom of the column, and which also traverse the liquid, will likewise not be free from fusel oils.

By the process already known the mixture of alcohol and water is diluted with water, and the fusel oils separated therefrom due to the dilution, and which float on the surface of the liquid, are withdrawn in liquid form from the column together with the superficial portion of the liquid. By my process the fusel oils are carried out of the column in vapor form together with the steam which is driven through the column, the arrangement being such that the molecules of fusel oil become incorporated with the particles of steam and quit the column in conjunction therewith. In order to avoid as far as possible any absorption of alcohol vapors by the steam, while this latter is being conducted through the column, it is preferable -to allow the steam to pass through the column as quickly as possible. After the fusel oils have been removed from the column together with the steam, they are then liquefied. To effect this the steam combined with the fusel oils is conductedfusel oils are consequently concentrated The best means of effecting this is to use an auxiliary evaporator or so-called after affected and separate in the liquid form.

Steam is best introduced into the column at the locality of the so-called dividing layer in two ways: first, below the surface of the liquid collected on the bottom of the tray in that locality of the still, whereby the supernatant layer of fusel oils may be vaporized into the space above the tray; and second, by introducing the steam into the space above the liquid in such a manner as to give the vapors a substantially horizontal whirling motion. A suitable perforated withdrawal pipe arranged in the path of the whirling layer or zone of mixed steam and fusel oil vapors, serves as means for withdrawing such mixed vapors and discharging them to some convenient point outside the column. Steam may be introduced at a temperature of about 100 C., and should equal in quantity about 10 per cent. of that re quired for the whole distilling processes.

In order to renderthe invention clearly comprehensible, reference is made by way of example to the accompanying drawing, showing an apparatus for carrying out the invention in a suitable manner.

In this illustration, Figure l is a fragmentary vertical section of a. portion of a column arranged as a sort of trap; Fig. 2 is a fragmentary vertical section of a distilling column, taken in the vicinity of the dividing layer; and Fig. 3 is a horizontal sec tion of Fig. 2 in the vicinity of pipes 3 and 4t. I

Referring to the drawings, 1 represents a compartment of the distilling column.

This column may comprise any suitable number of compartments superposed and in communication with each other. The particular compartment here illustrated is that located substantially at the so-called dividing layer where the fusel oils still remain undissolved, and just below the locality in the column where the alcoholic vapors become strong enough to dissolve the fuscl oils. In practice, this compartment may be the fifth compartment -from the bottom, assuming the still to be of the dimensions and to have the number of floors hereinbefore mentioned. a

Near the bottom of the lower tray in compartment 1 is arranged circular perforated steam pipe 2 supplied with steam from any chamber.

ber 1 and tangentially to the walls thereof.-

Suitably spaced from steampipe 3 and at about the same level is arranged perforated. pipe 4 whichprojects radially into the vapor Pipe 4 is provided to withdraw.

from the vapor chamber mixed vapors of 'steam and fusel oils.

The method of using the described apparatus in carrying out the process of the present invention is substantially as follows. Steam being admitted beneath the level of the liquid in the bottom of the compartment to perforated pipe 2, mixed vapors of steam and fusel oils fill the vapor space, and are caused to assume a whirling movement in a substantially horizontal plane by the introduction ofsteam through the nozzles in pipe 3. Through perforated pipe 4 the mixed vapors are continuously withdrawn, the whirling movement given by the tangentially directed jets of steam to the layer of mixed vapors serving to constantly present new quantities of the mixed vapors to the withdrawal pipe.

In Fig. l is illustrated a kind of trap for preventing return of the fusel oils from the base of the distilling column to the still immediately therebelow. This trap is located at a level below that portion of the still shown in Fig. 2, and is advantageously employed with the means hereinbefore described in carryingout the present process.

37 is a wide cylindrical tube open at both ends and having its upper and lower edges ,slotted or serrated. as shown to favor the passage of liquid along the walls of the conduit without interfering with the upward passage of vapors from the still. Surrounding 37 and spaced away therefrom is a cylindrical baflie 38 which projects above the edges of 37 and extends downwardly toward the bottom of the compartment, stopping short thereof however. 39 is a pipe through which return condensed liquids from the upper part of the apparatus and 40 is a cup-shaped member receiving the open end of said pipe. 41 is a circular perforated pipe for supplying steam. Liquid flowing into the compartment from pipe 39 fills the compartment to about the level of the upper edge of member 37. The strength of this alcoholicliquor is such that fusel oils contained therein are not dissolved but accumulate as a supernatant liquid layer onthe surfaceof the liquid in the compartment.' This supernatant layer is prevented by baffle 88 from access to the space between 37 and 38. The heavier alcoholic liquid however fiowsunder the edge of 38 and over the upper edge of 37 and thence downwardly into the still. Steam being introduced through perforated pipe 41, mixed vapors of steam and fusel oil,

containing of course'some alcohol, fill the space above the liquid and pass upwardly through the compartments of the column, ultimately arriving at compartment 1, where the withdrawal of mixed vapors and steam and fusel oils is effected as described.

The apparatus described and shown and advantageously used in performing the described process forms the subject matter of y 27 3,292, filed August 8, 1905.

Having now described my invention and explained the manner in which it is to be performed, I declare that what I claim as my invention and desire to secure by Letters Patent is as follows:

1. A process for the removal of the fusel oils, during the distillation and rectification of alcohol, from the mixture of water, alcohol and fusel oilpresent in the distilling and rectifying column, consisting in introducing steam into the column, at the point where the fusel .oils' begin to dissolve slightly in the alcoholic mixture but neverco-pending application Serial No.

theless substantially the whole of such oils 7 still remain undissolved, and withdrawing the steam mixed with fusel oil vapors from the column at another point situated at a certain distance away.

2. The process of separating the first and last runnings during the distillation and rectification of alcoholic liquids, which comprises carrying on such distillation and rectification in a suitable column apparatus, introducing steam into such-column near the locality where the fusel oils are about to dissolve, but still remain substantially. undissolved, maintaining a whirling layer of mixed vapors of fusel oils and steam in such locality, withdrawing such mixed vapors from the whirling layer and discharging the same outside of the column.

In testimony that I claim the foregoingas my invention, I have signed my name in presence of two subscribing witnesses.

FRANZ PAMPE.

Witnesses RUDOLPH FRICKE, S. P. WARNER. 

